A population-based observational study was published by Sun et al, to estimate the global prevalence of blindness and vision loss caused by glaucoma, and to evaluate the impact of socioeconomic factors on it.
The prevalence of blindness and vision loss due to glaucoma were obtained from the Global Burden of Disease Study 2017 database. The Human Development Index (HDI), inequality-adjusted HDI and other socioeconomic data were acquired from international open databases.
In 2020, glaucoma caused 11% of all global blindness in adults aged 50 years and older.
In 2020, 4.13 million people aged 50 years and older suffered moderate and severe vision impairment, and 3.6 million were blind due to glaucoma.
The prevalence of glaucoma varies among different nations and regions. It appears to be highest among persons of African descent (ranging from 6.5% to 7.3%), followed by East Asian populations (ranging from 2.59% to 3.54%). This may be compared with figures from European-derived populations, which have been reported to fall below 2.0%.
The overall prevalence worldwide was 81.5 (95% CI 69.9 to 95.0) per 100 000 in 1990 and 75.6 (95% CI 65.0 to 88.1) per 100 000 in 2017. The age-standardised prevalence of cases per 100 000 in 2017 was highest in African region (171.5, 95% CI 146.9 to 200.2) and lowest in Region of the Americas (61.1, 95% CI 52.6 to 70.7).
In terms of annual change between 1990 and 2017, the greatest increase in the prevalence was in Côte d’Ivoire (108.3) per 100,000, while the greatest decrease was in Qatar (−167.1) per 100 000.
The prevalence of blindness and vision loss due to glaucoma in 2017 among men was higher than that among women (men vs women：6.07, 95% CI 3.79 to 8.81 vs 5.42, 95% CI 3.40 to 7.81) per 100 000. The prevalence for both sexes increased as age rose from 45 years to 95 years.
Among the six WHO regions, the highest age-standardised prevalence of blindness and vision loss due to glaucoma was in the Eastern Mediterranean between 1990 and 2005 and in the African region between 2006 and 2017. By contrast, the region of the Americas had the lowest prevalence during the most period from 1990 to 2017 (63.0 per 100 000 in 1990, and 61.1 per 100 000 in 2017).
With respect to income, the highest age-standardised prevalence was found in the World Bank’s low-income regions (157.2 per 100 000 in 2017), while the lowest prevalence was found in high-income regions (42.7 per 100 000 in 2017) with statistical significance (p<0.001).
Similarly, the age-standardised prevalence was highest in low-SDI regions (111.2 per 100 000 in 2017) and lowest in high-SDI level regions (40.3 per 100 000 in 2017) (p<0.001). SDI is a measure of sociodemographic development based on educational attainment, average income per capita and total fertility rate. SDI varies from 0 to 1, and a higher value suggests a higher educational attainment and per capita income, and a lower total fertility rate.
The results showed that the worldwide age-standardised prevalence of blindness and vision loss due to glaucoma decreased from 81.5 per 100 000 in 1990 to 75.6 per 100 000 in 2017, and the prevalence increased with age and is higher among men.
GNI per capita, expected years of schooling and age-standardised prevalence of cataract and refractive disorder was the associated factors with the prevalence of blindness and vision loss due to glaucoma when adjusting for the influence of socioeconomic factors and healthcare indicators.
Although the number of glaucoma patients aged 40–80 years was predicted to increase to 76 million in 2020, and the number of blind or visually impaired due to glaucoma increased by 0.8 million and 2.3 million from 1990 to 2010, respectively, age-standardised prevalence of blindness and vision loss due to glaucoma decreased between 1990 and 2017. This may be mainly explained by the revolution in diagnostic methods such as optical coherence tomography (OCT), OCT angiography and automated perimetry, which has made early detection of asymptomatic glaucoma possible, at least in high-income countries, where access to such technology is better.
REFERENCE:
Sun Y, Chen A, Zou M, Zhang Y, Jin L, Li Y, Zheng D, Jin G, Congdon N. Time trends, associations and prevalence of blindness and vision loss due to glaucoma: an analysis of observational data from the Global Burden of Disease Study 2017. BMJ Open. 2022 Jan 6;12(1):e053805. doi: 10.1136/bmjopen-2021-053805. PMID: 34992115; PMCID: PMC8739070.
